MANCHESTER, Tennessee -- Jason Isbell is known for writing intimate story-songs, with lyrics that fill listeners' heads with images and mini-movies.

Yet he and his potent band the 400 Unit filled Bonnaroo's headliner-sized Which Stage just fine during his June 14 afternoon performance at the festival.

Isbell's set was in balance. Older songs that had the sun-soaked Bonnaroo day two crowd in the front singing the words back to him ("Codeine," "Outfit") as well as material from his sharp new album "Southeastern" ("Flying Over Water") that seems destined for the same place in his fans' lives. Personal acoustic material ("Cover Me Up") was weaved with loud electric stompers (the Neil Young & Crazy Horse nod "Stockholm").

In fine voice throughout his Bonnaroo set, Isbell's vocals seemed to soar higher the deeper into the afternoon he got. The Muscle Shoals-area native's wife - the very pretty, very petite Amanda Shires - played the entire set with the 400 Unit, adding sweet harmonies and Southern Gothic violin lines.

Whenever the band locked in and was really cooking, Isbell would shoot Shires a toothy grin.

Isbell, wearing dark wayfarer shades, jeans and a black short-sleeve shirt, stepped out for several lengthy electric solos on his goldtop Dussenberg guitar, often walking to the edge of the stage to rain distortion over the crowd.

Picking his Martin acoustic back up, Isbell led the 400 Unit through wintry ballad "Travelin' Alone," a tune that suggests if he ever wanted to sell a million records as a country artist, he could do so.

Now based in Nashville, Isbell closed his set with authority, with a hot, swaggering version of his Mick-and-Keith-worthy rocker from "Southeastern," "Super 8."

He thanked and waved to the Bonnaroo crowd. And walked off stage like a man enjoying another jewel of a day in the prime of his life.